The present disclosure relates to a multilayer ceramic capacitor and a board having the same.
A multilayer ceramic capacitor (MLCC), a multilayer chip electronic component, may be used in various electronic apparatuses due to advantages thereof, such as a small size, high capacitance, and ease of mounting.
For example, the multilayer ceramic capacitor may be used as a chip type condenser installed on the boards of various electronic products such as display devices, for example, liquid crystal displays (LCDs), plasma display panels (PDPs), and the like, as well as computers, personal digital assistants (PDAs), and a mobile phones, serving to charge electricity in the batteries thereof or discharge electricity therefrom.
Multilayer ceramic capacitors may have a structure in which a plurality of dielectric layers and internal electrodes having different polarities with respective dielectric layers interposed therebetween are alternately disposed.
In this case, since the dielectric layer has piezoelectric properties, when a direct current (DC) or alternating current (AC) voltage is applied to the multilayer ceramic capacitor, a piezoelectric phenomenon may occur between the internal electrodes, thereby causing periodic vibrations while expanding and contracting a volume of a ceramic body according to the frequency thereof.
These vibrations may be transferred to the board through external electrodes of the multilayer ceramic capacitor and solders connecting the external electrodes and the board to each other, such that the entire board may act as a sound reflecting surface, whereby vibration sound, commonly known as noise, may occur.
This vibration sound may correspond to an audio frequency range of 20 to 20,000 Hz causing listener discomfort. This vibration sound causing listener discomfort, as described above, is known as acoustic noise.
In addition, as noiseless components have been provided in electronic equipment, the acoustic noise caused by the multilayer ceramic capacitor as described above may appear relatively more significantly.
Moreover, when equipment is operated in a relatively silent environment, users may perceive such acoustic noise as equipment component failure.
In addition, in the equipment having voice circuits, acoustic noise may be overlapped with voice output, which may cause a problem in which equipment has deteriorated quality in audio output.